View Source imglab
imglab
is the official Elixir library to integrate with imglab services.
installation
Installation
Add imglab
to your list of dependencies in mix.exs
:
def deps do
[
{:imglab, "~> 0.2"}
]
end
And run:
$ mix deps.get
elixir-compatibility
Elixir compatibility
imglab
has been successfully tested on the following Elixir versions: 1.13
, 1.12
, 1.11
, 1.10
, 1.9
, 1.8
, 1.7
, 1.6
, 1.5
, and 1.4
.
generating-urls
Generating URLs
You can use Imglab.url/3
function to generate imglab compatible URLs for your application.
The easiest way to generate a URL is to specify the source_name
, path
and required parameters
:
Imglab.url("assets", "image.jpeg", width: 500, height: 600)
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600"
Imglab.url("avatars", "user-01.jpeg", width: 300, height: 300, mode: :crop, crop: :face, format: :webp)
"https://avatars.imglab-cdn.net/user-01.jpeg?width=300&height=300&mode=crop&crop=face&format=webp"
If some specific settings are required for the source you can use a Imglab.Source
struct instead of a string
source name:
Imglab.url(Imglab.Source.new("assets"), "image.jpeg", width: 500, height: 600)
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600"
using-secure-image-sources
Using secure image sources
For sources that require signed URLs you can specify secure_key
and secure_salt
attributes:
"assets"
|> Imglab.Source.new(secure_key: "assets-secure-key", secure_salt: "assets-secure-salt")
|> Imglab.url("image.jpeg", width: 500, height: 600)
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&signature=generated-signature"
signature
query parameter will be automatically generated and attached to the returned URL.
Note:
secure_key
andsecure_salt
attributes are secrets that should not be added to a code repository. Please use environment vars or other secure method to use them in your application.
using-http-instead-of-https
Using HTTP instead of HTTPS
In the case that HTTP schema is required instead of HTTPS you can set https
attribute to false
when creating the source:
"assets"
|> Imglab.Source.new(https: false)
|> Imglab.url("image.jpeg", width: 500, height: 600)
"http://assets.imglab-cdn.net/image.jpeg?width=500&height=600"
Note: HTTPS is the default and recommended way to generate URLs with imglab.
specifying-parameters
Specifying parameters
Any parameter from the imglab API can be used to generate URLs with Imglab.url/3
function. For parameters that required dashes characters like trim-color
you can use regular underscore Elixir atoms like :trim_color
those will be normalized in the URL generation to it's correct form:
Imglab.url("assets", "image.jpeg", trim: "color", trim_color: "black")
"https://assets.imglab-cdn.net/image.jpeg?trim=color&trim-color=black"
It is possible to use quoted atoms too:
Imglab.url("assets", "image.jpeg", trim: "color", "trim-color": "black")
"https://assets.imglab-cdn.net/image.jpeg?trim=color&trim-color=black"
specifying-color-parameters
Specifying color parameters
Some imglab parameters can receive a color as value. It is possible to specify these color values as strings:
# Specifying a RGB color as string
Imglab.url("assets", "image.jpeg", width: 500, height: 600, mode: :contain, background_color: "255,0,0")
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&mode=contain&background-color=255%2C0%2C0"
# Specifying a RGBA color as string
Imglab.url("assets", "image.jpeg", width: 500, height: 600, mode: :contain, background_color: "255,0,0,128")
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&mode=contain&background-color=255%2C0%2C0%2C128"
# Specifying a named color as string
Imglab.url("assets", "image.jpeg", width: 500, height: 600, mode: :contain, background_color: "red")
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&mode=contain&background-color=red"
# Specifying a hexadecimal color as string
Imglab.url("assets", "image.jpeg", width: 500, height: 600, mode: :contain, background_color: "F00")
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&mode=contain&background-color=F00"
You can additionally use Imglab.Color
macros to specify these color values:
# Remember to import Imglab.Color before use these macros
import Imglab.Color
# Using color macro for a RGB color
Imglab.url("assets", "image.jpeg", width: 500, height: 600, mode: "contain", background_color: color(255, 0, 0))
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&mode=contain&background-color=255%2C0%2C0"
# Using color macro for a RGBA color
Imglab.url("assets", "image.jpeg", width: 500, height: 600, mode: "contain", background_color: color(255, 0, 0, 128))
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&mode=contain&background-color=255%2C0%2C0%2C128"
# Using color macro for a named color
Imglab.url("assets", "image.jpeg", width: 500, height: 600, mode: "contain", background_color: color("red"))
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&mode=contain&background-color=red"
Note: specify hexadecimal color values using
Imglab.Color
macros is not allowed. You can use strings instead.
specifying-position-parameters
Specifying position parameters
Some imglab parameters can receive a position as value. It is possible to specify these values using strings:
# Specifying a horizontal and vertical position as string
Imglab.url("assets", "image.jpeg", width: 500, height: 500, mode: "crop", crop: "left,top")
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=500&mode=crop&crop=left%2Ctop"
# Specifying a vertical and horizontal position as string
Imglab.url("assets", "image.jpeg", width: 500, height: 500, mode: "crop", crop: "top,left")
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=500&mode=crop&crop=top%2Cleft"
# Specifying a position as string
Imglab.url("assets", "image.jpeg", width: 500, height: 500, mode: "crop", crop: "left")
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=500&mode=crop&crop=left"
You can additionally use Imglab.Position
macros to specify these position values:
# Remember to import Imglab.Position before use these macros
import Imglab.Position
# Using position macro for a horizontal and vertical position
Imglab.url("assets", "image.jpeg", width: 500, height: 500, mode: "crop", crop: position("left", "top"))
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=500&mode=crop&crop=left%2Ctop"
# Using position macro for a vertical and horizontal position
Imglab.url("assets", "image.jpeg", width: 500, height: 500, mode: "crop", crop: position("top", "left"))
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=500&mode=crop&crop=top%2Cleft"
# Using position macro for a position
Imglab.url("assets", "image.jpeg", width: 500, height: 500, mode: "crop", crop: position("left"))
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=500&mode=crop&crop=left"
specifying-url-parameters
Specifying URL parameters
Some imglab parameters can receive URLs as values. It is possible to specify these parameter values as strings.
Imglab.url("assets", "image.jpeg", width: 500, height: 600, watermark: "logo.svg")
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&watermark=logo.svg"
And even use parameters if required:
Imglab.url("assets", "image.jpeg", width: 500, height: 600, watermark: "logo.svg?width=100&format=png")
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&watermark=logo.svg%3Fwidth%3D100%26format%3Dpng"
Additionally you can use nested Imglab.url/3
calls to specify these URL values:
Imglab.url(
"assets",
"image.jpeg",
width: 500,
height: 600,
watermark: Imglab.url("assets", "logo.svg", width: 100, format: "png")
)
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&watermark=https%3A%2F%2Fassets.imglab-cdn.net%2Flogo.svg%3Fwidth%3D100%26format%3Dpng"
If the resource is located in a different source we can specify it using Imglab.url/3
:
Imglab.url(
"assets",
"image.jpeg",
width: 500,
height: 600,
watermark: Imglab.url("marketing", "logo.svg", width: 100, format: "png")
)
"https://assets.imglab-cdn.net/image.jpeg?width=500&height=600&watermark=https%3A%2F%2Fmarketing.imglab-cdn.net%2Flogo.svg%3Fwidth%3D100%26format%3Dpng"
Using secure sources for URLs parameter values is possible too:
marketing_source = Imglab.Source.new("marketing", secure_key: "marketing-secure-key", secure_salt: "marketing-secure-salt")
Imglab.url(
"assets",
"image.jpeg",
width: 500,
height: 600,
watermark: Imglab.url(marketing_source, "logo.svg", width: 100, format: "png")
)
signature
query parameter will be automatically generated and attached to the nested URL value.
generating-urls-for-on-premises-imglab-server
Generating URLs for on-premises imglab server
For on-premises imglab server is possible to define custom sources pointing to your server location.
:https
- aboolean
value specifying if the source should use https or not (default:true
):host
- astring
specifying the host where the imglab server is located. (default:imglab-cdn.net
):port
- a:inet.port_number
specifying a port where the imglab server is located.:subdomains
- aboolean
value specifying if the source should be specified using subdomains instead of using the path. (default:true
)
If we have our on-premises imglab server at http://my-company.com:8080
with a source named images
we can use the following source settings to access a logo.png
image:
"images"
|> Imglab.Source.new(https: false, host: "my-company.com", port: 8080)
|> Imglab.url("logo.png", width: 300, height: 300, format: "png")
"http://images.my-company.com:8080/logo.png?width=300&height=300&format=png"
It is possible to use secure sources too:
"images"
|> Imglab.Source.new(https: false, host: "my-company.com", port: 8080, secure_key: "images-secure-key", secure_salt: "images-secure-salt")
|> Imglab.url("logo.png", width: 300, height: 300, format: "png")
"http://images.my-company.com:8080/logo.png?width=300&height=300&format=png&signature=generated-signature"
using-sources-with-disabled-subdomains
Using sources with disabled subdomains
In the case that your on-premises imglab server is configured to use source names as paths instead of subdomains you can set subdomains
attribute to false
:
"images"
|> Imglab.Source.new(https: false, host: "my-company.com", port: 8080, subdomains: false)
|> Imglab.url("logo.png", width: 300, height: 300, format: "png")
"http://my-company.com:8080/images/logo.png?width=300&height=300&format=png"
license
License
imglab source code is released under MIT License.